Hi, everyone! I'm Katie Zhang from Acton, Massachusetts. I'm a nerd in every sense of the word. I like playing the trombone, video games, and of course, science. Ever since 7th grade, biology has always been fascinating to me, to the point where I want to make a career out of it. Despite this, however, I'm still a little unsure about which specific field of biology to focus on. I hope that through this camp, I'll get a good sense of what being a synthetic biologist is like, adding to my list of possibilities. I'm planning to begin competing on my school's Science Olympiad team next year. I'm looking forward to meeting and working with you all!
Design Project: Dust-eating Amoeba
70% of household dust is made up of dead human skin cells. Dust mites are microscopic arthropods that feed on these skin cells.
When an individual has a dust allergy, they are not reacting to the dust itself, but rather the dust mites and their feces. The current treatments for dust allergies range from ridding the house of dust by constantly cleaning and dehumidifying rooms, to using medical assistance like medication and immunotherapy. However, having to constantly clean the house is time-consuming, and using medication or taking immunotherapy can be expensive. Medication must be regularly replaced and paid for, and immunotherapy is expensive. A 1 fluid ounce of dust-allergy relief costs $11.49, and immunotherapy shots cost between $800-$1000 per year. Immunotherapy takes about 3-5 years to complete.
One potential solution is to genetically engineer an amoeba that can consume the alpha-keratin in human skin cells. In large enough numbers, the amoeba can outcompete the mites by taking away their only food source. In addition, the amoeba can also consume dust mite feces, as it consists of 3-5 balls of digested food stuck together by mucus. The dust mites do not consume anything other than skin, meaning that they cannot stop the amoeba from eating skin as well.
The amoeba that would be used would be Chilomastix mesnili.
This amoeba is found in the intestinal tract of humans, is considered nonpathogenic to humans by the Center for Disease Control and Prevention(CDC), and is 6-24 micrometers in diameter. Since a skin cell is usually about 30 micrometers in diameter, these amoeba would easily be able to consume 1 cell alone. The genes that would be inserted code for the production of proteolytic and disulfide bond-reducing proteins, which work in conjunction to efficiently break down keratin. These genes do not have official names. These genes can both be extracted from the bacteria Stentrophomonas Sp. , which can be isolated from deer fur.
The reason that amoeba are used instead of this bacterium is for three reasons. First, amoeba are larger. This means that they can consume bigger bits of food and will require more energy from food. Therefore, they can consume and break down the cells faster than a bacterium can. Second, amoeba live longer than bacteria. A bacterium only lives about 12-24 minutes, while an amoeba lives about two hours. While it may seem logical to use a bacteria in this case, since bacteria reproduce very frequently due to their very short life spans, there is a much smaller chance of total population dying in organisms with longer life spans. If the bacteria completely clean out a particular area of skin cells, they might not be able to make it to an area more concentrated with skin. Amoeba, on the other hand, have a much better likelihood of migrating to an area with more food due to their longer lifespan. Third, the bacteria may not be safe. Not much is known about the genus Stentrophomonas, though some species are considered pathogenic to humans. For safety, the bacteria should not be used as the final product, because it may harm humans as it is, or mutate into a harmful pathogen.
The product would be in the form of a spray bottle. The amoeba would contain the amoeba in high concentrations along with a secondary food source to keep them alive for a certain period of time. All the particles are suspended in fresh water, the amoeba’s natural habitat. The consumer sprays to apply the mix.
The amoeba would respond to the presence of alpha-keratin in its environment. After it consumes the cell, the amoeba can break down the protein into components that it can use. The genes would be activated when the cell senses alpha-keratin nearby. On the other hand, if no keratin is detected, then the genes turn off. The genetic components necessary are: a receptor that binds to alpha-keratin, promoters that control the genes for synthesizing these proteins, repressors for the promoters to repress the gene when no keratin is detected, a binding site, and the genes that code for proteolytic and disulfide bond-reducing proteins.
Presence of ⍺-keratin
Proteolytic and disulfide bond-reducing proteins
0
0
1
1
If the system works perfectly, the expected result should be less dust and less dust mite feces in the household, greatly reducing, if not completely eliminating, the main trigger for both dust allergies and asthma.
This product will be better than the current technologies because it will be much cheaper than immunotherapy or medication, and much faster than cleaning and dusting the house. It will also be very cost-effective. The amoeba can easily be extracted from human feces, the bacteria can be taken from deer fur, a common woodland animal, and the spray bottle only costs about 5-15 cents a piece. However, there are some problems to this design that must be addressed. There are three major issues that can be hazardous to people. First, Chilomastix mesnili, like other nonpathogenic, gastrointestinal amoeba, has been known to generate false positives and false negatives when being tested for a amoeba-borne disease. A possible solution to this issue is to let doctors know that the user has been in close contact with Chilomastix mesnili, that it is not harmful, and that they should ignore it if it is found in the body. Second, and more severely, there needs to be a way for the amoeba to not consume live skin cells. Epidermal cells contain the same material, living or dead. One solution would be to insert a gene that forces the amoeba to commit suicide if it detects too many living cells and their secretions. If it detects a large presence of substances that living skin secretes, like sweat or oils, the lethal gene is activated. Third, there is the possibility that the amoeba can mutate such that they become ineffective or worse, become harmful towards people or animals. If this happens, a different spray can be developed and provided with the original product that will kill the amoeba quickly to prevent further issues. A less severe issue is that the amoeba may be more or less effective in certain temperatures and humidities than in others. That means that the product will be less effective in some household than in others. To remedy this problem, the consumer can use humidifiers, dehumidifiers, air conditioners, and heaters to manipulate their environment to fit the optimal conditions. While there are certainly some pressing issues in the use of this product, there are solutions for all of these problems that are safely within the realm of probability and can be executed with some more time taken. With these issues settled, there should be no inhibition or hesitation to produce this product.
To test this product, there should be multiple test rooms with typical furnishings. The control rooms should have dust and mites, and have varying temperatures and humidities. No spray should be applied in the control rooms. The test rooms should each have conditions matching one of the control rooms. In these rooms, the spray is applied. The spray is applied to every spot in the room and regularly for a week. Before the spray is applied, a set number of dust mites is released into the room, and a similar density of dust is layered in the room. After a week has passed, data is collected. In each room, the new density of dust (per square cm.), the new approximate amount of live dust mites, and the new approximate number of amoeba is recorded. From this data, it tests 1) how effective the product is at doing what it is intended to do, and 2) what the best conditions for the amoeba are. From this data, directions on the spray bottle can be written accordingly to notify the customer of what the recommended environment should be, so they can adjust accordingly to enjoy the benefits of the product.
“Allergy Shots (Immunotherapy) | AAAAI.” The American Academy of Allergy, Asthma & Immunology, www.aaaai.org/conditions-and-treatments/treatments/allergy-shots-(immunotherapy). Accessed 11 July 2017.
“BioAllers Allergy Treatment, Mold, Yeast & Dust - 1 Fl Oz.” Google, Google, www.google.com/shopping/product/4087770873150594772?lsf=seller%3A15646%2Cstore%3A483471337475313005&prds=oid%3A9595957822281025622&q=allergy%2Bmedicine%2Bfor%2Bdust&hl=en&ei=7EleWeqoFsv4jwTN4pOACA&lsft=gclid%3ACj0KEQjwv_fKBRCG8a3ao-OQuZ8BEiQAvpHp6KgTkGmzTWEt0w7IRje88blzG__lv0s8EkTlEjwTIygaAntq8P8HAQ. Accessed 11 July 2017.
“Chilomastix Mesnili - Overview.” Encyclopedia of Life, eol.org/pages/12154845/overview. Accessed 11 July 2017.
“The Draft Genome, Transcriptome, and Microbiome of Dermatophagoides Farinae Reveal a Broad Spectrum of Dust Mite Allergens.” The Draft Genome, Transcriptome, and Microbiome of Dermatophagoides Farinae Reveal a Broad Spectrum of Dust Mite Allergens - ScienceDirect, www.sciencedirect.com/science/article/pii/S0091674914013669. Accessed 11 July 2017.
“Dust Allergy.” ACAAI Public Website, acaai.org/allergies/types/dust-allergy. Accessed 11 July 2017.
Mite, House Dust. “All about House Dust Mite Droppings.” House Dust Mite Allergy Site, housedustmite.com/all-about-mite-droppings. Accessed 11 July 2017.
“Parasites - Nonpathogenic (Harmless) Intestinal Protozoa.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 14 Dec. 2012, www.cdc.gov/parasites/nonpathprotozoa/. Accessed 11 July 2017.
“The Role of Chemistry in History.” The Role of Chemistry in History RSS, itech.dickinson.edu/chemistry/?cat=69. Accessed 11 July 2017.
“Spray Bottle.” Spray Bottle, Spray Bottle Suppliers and Manufacturers at Alibaba.com, www.alibaba.com/showroom/spray-bottle.html. Accessed 11 July 2017.
Design Project: Dust-eating Amoeba
70% of household dust is made up of dead human skin cells. Dust mites are microscopic arthropods that feed on these skin cells.
When an individual has a dust allergy, they are not reacting to the dust itself, but rather the dust mites and their feces. The current treatments for dust allergies range from ridding the house of dust by constantly cleaning and dehumidifying rooms, to using medical assistance like medication and immunotherapy. However, having to constantly clean the house is time-consuming, and using medication or taking immunotherapy can be expensive. Medication must be regularly replaced and paid for, and immunotherapy is expensive. A 1 fluid ounce of dust-allergy relief costs $11.49, and immunotherapy shots cost between $800-$1000 per year. Immunotherapy takes about 3-5 years to complete.
One potential solution is to genetically engineer an amoeba that can consume the alpha-keratin in human skin cells. In large enough numbers, the amoeba can outcompete the mites by taking away their only food source. In addition, the amoeba can also consume dust mite feces, as it consists of 3-5 balls of digested food stuck together by mucus. The dust mites do not consume anything other than skin, meaning that they cannot stop the amoeba from eating skin as well.
The amoeba that would be used would be Chilomastix mesnili.
This amoeba is found in the intestinal tract of humans, is considered nonpathogenic to humans by the Center for Disease Control and Prevention(CDC), and is 6-24 micrometers in diameter. Since a skin cell is usually about 30 micrometers in diameter, these amoeba would easily be able to consume 1 cell alone. The genes that would be inserted code for the production of proteolytic and disulfide bond-reducing proteins, which work in conjunction to efficiently break down keratin. These genes do not have official names. These genes can both be extracted from the bacteria Stentrophomonas Sp. , which can be isolated from deer fur.
The reason that amoeba are used instead of this bacterium is for three reasons. First, amoeba are larger. This means that they can consume bigger bits of food and will require more energy from food. Therefore, they can consume and break down the cells faster than a bacterium can. Second, amoeba live longer than bacteria. A bacterium only lives about 12-24 minutes, while an amoeba lives about two hours. While it may seem logical to use a bacteria in this case, since bacteria reproduce very frequently due to their very short life spans, there is a much smaller chance of total population dying in organisms with longer life spans. If the bacteria completely clean out a particular area of skin cells, they might not be able to make it to an area more concentrated with skin. Amoeba, on the other hand, have a much better likelihood of migrating to an area with more food due to their longer lifespan. Third, the bacteria may not be safe. Not much is known about the genus Stentrophomonas, though some species are considered pathogenic to humans. For safety, the bacteria should not be used as the final product, because it may harm humans as it is, or mutate into a harmful pathogen.
The product would be in the form of a spray bottle. The amoeba would contain the amoeba in high concentrations along with a secondary food source to keep them alive for a certain period of time. All the particles are suspended in fresh water, the amoeba’s natural habitat. The consumer sprays to apply the mix.
The amoeba would respond to the presence of alpha-keratin in its environment. After it consumes the cell, the amoeba can break down the protein into components that it can use. The genes would be activated when the cell senses alpha-keratin nearby. On the other hand, if no keratin is detected, then the genes turn off. The genetic components necessary are: a receptor that binds to alpha-keratin, promoters that control the genes for synthesizing these proteins, repressors for the promoters to repress the gene when no keratin is detected, a binding site, and the genes that code for proteolytic and disulfide bond-reducing proteins.
If the system works perfectly, the expected result should be less dust and less dust mite feces in the household, greatly reducing, if not completely eliminating, the main trigger for both dust allergies and asthma.
This product will be better than the current technologies because it will be much cheaper than immunotherapy or medication, and much faster than cleaning and dusting the house. It will also be very cost-effective. The amoeba can easily be extracted from human feces, the bacteria can be taken from deer fur, a common woodland animal, and the spray bottle only costs about 5-15 cents a piece. However, there are some problems to this design that must be addressed. There are three major issues that can be hazardous to people. First, Chilomastix mesnili, like other nonpathogenic, gastrointestinal amoeba, has been known to generate false positives and false negatives when being tested for a amoeba-borne disease. A possible solution to this issue is to let doctors know that the user has been in close contact with Chilomastix mesnili, that it is not harmful, and that they should ignore it if it is found in the body. Second, and more severely, there needs to be a way for the amoeba to not consume live skin cells. Epidermal cells contain the same material, living or dead. One solution would be to insert a gene that forces the amoeba to commit suicide if it detects too many living cells and their secretions. If it detects a large presence of substances that living skin secretes, like sweat or oils, the lethal gene is activated. Third, there is the possibility that the amoeba can mutate such that they become ineffective or worse, become harmful towards people or animals. If this happens, a different spray can be developed and provided with the original product that will kill the amoeba quickly to prevent further issues. A less severe issue is that the amoeba may be more or less effective in certain temperatures and humidities than in others. That means that the product will be less effective in some household than in others. To remedy this problem, the consumer can use humidifiers, dehumidifiers, air conditioners, and heaters to manipulate their environment to fit the optimal conditions. While there are certainly some pressing issues in the use of this product, there are solutions for all of these problems that are safely within the realm of probability and can be executed with some more time taken. With these issues settled, there should be no inhibition or hesitation to produce this product.
To test this product, there should be multiple test rooms with typical furnishings. The control rooms should have dust and mites, and have varying temperatures and humidities. No spray should be applied in the control rooms. The test rooms should each have conditions matching one of the control rooms. In these rooms, the spray is applied. The spray is applied to every spot in the room and regularly for a week. Before the spray is applied, a set number of dust mites is released into the room, and a similar density of dust is layered in the room. After a week has passed, data is collected. In each room, the new density of dust (per square cm.), the new approximate amount of live dust mites, and the new approximate number of amoeba is recorded. From this data, it tests 1) how effective the product is at doing what it is intended to do, and 2) what the best conditions for the amoeba are. From this data, directions on the spray bottle can be written accordingly to notify the customer of what the recommended environment should be, so they can adjust accordingly to enjoy the benefits of the product.
Link to presentation:
https://docs.google.com/presentation/d/1_jV8mOiTDbLuSF4M7QQr50I5gnC74agwkS9NeVQsO24/edit?usp=sharing
Works cited:
“Allergy Shots (Immunotherapy) | AAAAI.” The American Academy of Allergy, Asthma & Immunology, www.aaaai.org/conditions-and-treatments/treatments/allergy-shots-(immunotherapy). Accessed 11 July 2017.
“BioAllers Allergy Treatment, Mold, Yeast & Dust - 1 Fl Oz.” Google, Google, www.google.com/shopping/product/4087770873150594772?lsf=seller%3A15646%2Cstore%3A483471337475313005&prds=oid%3A9595957822281025622&q=allergy%2Bmedicine%2Bfor%2Bdust&hl=en&ei=7EleWeqoFsv4jwTN4pOACA&lsft=gclid%3ACj0KEQjwv_fKBRCG8a3ao-OQuZ8BEiQAvpHp6KgTkGmzTWEt0w7IRje88blzG__lv0s8EkTlEjwTIygaAntq8P8HAQ. Accessed 11 July 2017.
“Chilomastix Mesnili - Overview.” Encyclopedia of Life, eol.org/pages/12154845/overview. Accessed 11 July 2017.
“The Draft Genome, Transcriptome, and Microbiome of Dermatophagoides Farinae Reveal a Broad Spectrum of Dust Mite Allergens.” The Draft Genome, Transcriptome, and Microbiome of Dermatophagoides Farinae Reveal a Broad Spectrum of Dust Mite Allergens - ScienceDirect, www.sciencedirect.com/science/article/pii/S0091674914013669. Accessed 11 July 2017.
“Dust Allergy.” ACAAI Public Website, acaai.org/allergies/types/dust-allergy. Accessed 11 July 2017.
Mite, House Dust. “All about House Dust Mite Droppings.” House Dust Mite Allergy Site, housedustmite.com/all-about-mite-droppings. Accessed 11 July 2017.
“Parasites - Nonpathogenic (Harmless) Intestinal Protozoa.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 14 Dec. 2012, www.cdc.gov/parasites/nonpathprotozoa/. Accessed 11 July 2017.
“The Role of Chemistry in History.” The Role of Chemistry in History RSS, itech.dickinson.edu/chemistry/?cat=69. Accessed 11 July 2017.
“Spray Bottle.” Spray Bottle, Spray Bottle Suppliers and Manufacturers at Alibaba.com, www.alibaba.com/showroom/spray-bottle.html. Accessed 11 July 2017.